BD (Blu-ray) technologies use a virtual file system (VFS) whereby a file acquired from a network and the like is stored in a local storage which is a different storage medium than a recording medium (referred to below as the “ROM disc”), such as a BD-ROM disc, a BD-R, and a BD-RE, and treated in a way as if it were recorded on the ROM disc.
In such a virtual file system, by mapping on the ROM disc one or more files stored in the local storage, files stored on the ROM disc and the files stored in the local storage are handled as data stored in a single virtual disc. The mapping makes use of a merge management information file which is a correspondence table between file paths in the virtual file system and file paths in the local storage. The single virtual disc recognized through the virtual file system is called a “virtual package”.
As one of conventional techniques regarding the virtual file system, Patent Literature 1 is known, for example.